Barbells are commonly used to perform a variety of exercises including curling and weightlifting, and it has been proposed to provide rotating handgrips for use in such apparatus so that the user's grip may be accommodated in any position and is not restricted to an angle parallel to the axis of the device. In particular, U.S. Pat. Nos. 3,384,370; 4,618,183; 4,629,184; 5,334,113; 6,022,300 and Re. 33,218 all disclose barbell arrangements having handgrips which are rotatably supported so that their angle relative to the bar may be adjusted.
One problem associated with prior art barbells resides in the fact that if the bar is to resist the bending forces imposed when the bar is lifted with weights on the end, it must be formed of a strong and relatively heavy material. The weight of this bar imposes a minimum weight on the exercise apparatus even without any end weights. Another problem is that the use of disk-like end weights creates problems in storage and transportation of a barbell with the associated weights.
Another problem associated with conventional barbells, with or without rotatable handgrips, is that it is inconvenient and awkward to provide a greater weight on one end than the other in order to impose asymmetrical stresses on the user's muscles during exercise.